The Home of Midwood Science Research

SEM image of the week: Turtle scutes

Posted on Monday, February 27, 2012 by for SEM.

One day, as I was walking with my sister on 5th avenue, I noticed a lady selling baby turtles. Each pair, one of each gender, was in a little tank. They looked absolutely adorable, I knew I just had to get one. My sister and I purchased one and practically ran home to show our mother. At first, she was furious because she isn’t a fan of pets, but over time, she grew to love them. After a week of ownership, the male turtle was dropped by my sister, and his soul was seized by death. The remaining female turtle, the one whose shell was observed under the microscope, was a lonely widow, so my mother decided to buy another pair of turtles. After she purchased another two, two years passed by and the male turtle grew more ill everyday. White foam escaped his mouth, and he was smaller and skinnier than the other two females. Eventually, he passed away and left the two widows alone.

Another year passed, and my neighbor came knocking on the door. He had just saved a turtle from getting run over by a car. He told us that he wouldn’t be able to take proper care of it so he wants us to keep it. Now, to this day, I haven’t named any of these turtles. I just can’t think of the perfect names for them. I call them turtles. I take them out for walks, as in I let them roam about the house freely, and when it’s good weather outside, I take them to the park. Usually, when I’m lonely, I actually talk to them. I know it’s weird since they can’t reply to me but it feels nice to have them there. I love my turtles, probably because they can’t be as evil as humans. They can’t backstab you, murder you, rob you, or anything of the sort. They’re amazing pets, and I’m glad to have them in my life.

My turtles are all classified as red eared sliders (Trachemys scripta elegant). If you notice in the pictures, the turtle has a red strip on each side of its head. The “slider” part of the name comes from their ability to slide off rocks and logs quickly. Red eared sliders are native to the southern United States but they’re found world wide because of turtle salesmen or travelers owning these pets. They’re actually the most popular pet turtle in the United States. They can be usually found in freshwater swamps. They love to hide around rocks but since they don’t have saliva, they’re forced to remain in water to eat their food. They’re omnivores and can eat a huge variety of foods including aquatic plants, fish, tadpoles, crickets, and worms. At home, I usually feed them shrimp, lettuce, and floating food sticks (which provide extra protein). The turtle’s outer shell is made of a thin layer of keratin, like your hair and fingernails, arranged in plates called scutes. Underneath that layer, there is a layer of bony plates, their ribs and vertebrae. My turtles shed scutes from time to time. I saved one to make the images below.

Overview showing the tip and central ridge of a scute. Note how the parallel machining lines of the metal platform are distorted due to charge accumulation on the edge of the scute. Flaking region at medium voltage and low vacuum. Flaking region at medium voltage and high vacuum.
Side view of the tip of a scute. Jagged edge of a broken scute. Jagged edge of a broken scute. The distortion that looks like smoke is caused by charge accumulation on a pointed region.
Scutes are made of interlocking plates of keratin. Some regions show texture under higher magnification. Underside of a scute showing indentations from blood vessels.

Image and text credit: Jasline Garcia. Caption credit: Glenn Elert